Contents

Objectives

Vehicle lanes with lane-specific turn restrictions

This proposal was set up with the following primary objectives in mind:

Reusing existing tags for maxspeed, access, surface, width …

Specifying full lane ordering. Example: The mapper should be able to not only express that cycleway and footway are both on the “left” side of the street, but also which of the two is further to the left.

Creating lanes with own geometries, e.g. for detailed mapping of complicated junctions.

Creating lanes without own geometries, e.g. for streets with perfectly parallel lanes where separate ways would make moving the street and similar actions unnecessarily difficult.

Compatibility with advanced information, such as lanes that connect to different streets and lane-specific turn restrictions. Example: In some situations (e.g. motorway junctions), it is helpful to know which lanes are intended for traveling straight on and which are intended for leaving the street. Ideally, an OSM-based navigation system could provide lane hints to a driver.

Concept

The features this proposal is based on are lanes (as lane ways or lane relations) and lane groups.

A lane way represents a single lane. It is tagged with the key lane and one of the values from the table at #lane values. With the exception of having a lane tag instead of a highway tag, this way can be tagged as usual, e.g. with access=*, surface=* …

A lane relation is an alternative to the lane way. It also represents a single lane, which is assumed to represent a lane parallel to the highway referenced in the lane_group. A lane relation needs no members and is tagged with type=lane. All other tags can be used as if it was a lane way.

By default, the lane is not available to any type of traffic that is not listed (access=no).

Note: This list is most probably incomplete and might require changes. Please use the talk page to comment on and discuss these values.

lane_group relation members

Type

Role

Recurrence

Description

highway

one

the highway the lanes belong to

none or number

one or more

lane that belongs to the highway's lane bundle – can be lane way or lane relationNumbering: You may use positive and negative numbers in a lane's role field to indicate their ordering – if lane “a” has a lower number than lane “b”, “a” is farther to the left than “b” (based on highway direction). A lane without number defaults to 0.Since API v0.6, the relation members' order can be used instead of explicit numbering. Lanes are supposed to be ordered from leftmost to rightmost lane.

Examples

Description

JOSM view

JOSM lanetool view

File link

two-lane road with a cycleway for each direction and a single footway. The mapper decided to draw one of the cycleways as an own way. The lanes have different surfaces (asphalt, cobblestone on the footway) and widths.